Web application on touch screen

I see your point, but let's consider the facts. The part of it is existing Web operation. It's good that you know how it works. Now, you see, touch screen specific behavior had never been a part of any Web standard. And the Web is essentially the set of standards (at least from what I know). If you take it in consideration with what you know about the Web operation, you will come to the same conclusion: the only way to support some touch screen specific behavior would be some particular browser's features. As the Web application cannot use any knowledge of the client system and particular browser, and touch screen related behavior is not standardized, you cannot modify the scripts, HTML, Javascript or something like that to work with touch screen. All you can do is making controls larger (so they can be manipulated with a thick finger) or something like that, pure stylistic changes.
--SA

You are perfectly right. In general, the standards like those related to Internet reflect typical state of the computing in general. When (and if) touch screen technologies perfect and become a common place, the might be embraced by Web. Look at the tabbed-style UI: many ask how to control the browser tabs by the Web applications, but it does not happen because Web is more conservative, and it makes perfect sense. Take your touch screen technologies... they are not yet there, and we don't know if they are going to became of commonplace ever, or not. Maybe they will be rendered obsolete before becoming common by some more effective technology, such as touchless gesture recognition, through a camera. What to do then?
--SA